Tapered optical fibers are promising one-dimensional nanophotonic waveguides that can provide efficient coupling between their fundamental mode and quantum nanoemitters placed inside them. Here, we present numerical studies on the coupling of single nitrogen-vacancy (NV) centers (single point dipoles) in nanodiamonds with tapered fibers. Our results lead to two important conclusions: (1) A maximum coupling efficiency of 53.4% can be realized for the two fiber ends when the NV bare dipole is located at the center of the tapered fiber. (2) NV centers even in 100-nm-sized nanodiamonds where bulk-like optical properties were reported show a coupling efficiency of 22% at the taper surface, with the coupling efficiency monotonically decreasing as the nanodiamond size increases. These results will be helpful in guiding the development of hybrid quantum devices for applications in quantum information science.

Thin films of As46Te46S8 with different thicknesses were prepared via thermal evaporation onto chemically cleaned glass substrates at different temperatures. X-ray diffraction of the deposited film at room temperature revealed the formation of an amorphous structure. In addition, the selected-area electron diffraction (SAED) patterns confirmed the amorphous phase. The mechanism of the optical absorption was observed to follow the rule of direct transition. An increase in the optical gap (E0) from 2.35 to 2.73 eV was observed when the substrate temperature TS was varied from room temperature to 463 K (film thickness = 100 nm). In addition, E0 was observed to be dependent on the film thickness and increased from 1.7 to 2.38 eV when the film thickness was increased from 35 to 135 nm (TS = room temperature). The effect of TS on the electrical properties was also studied. The electrical resistivity (ρ) and the activation energy for conduction ( E ) decreased from 7.74 x105 to 6.81 x 102 Ω cm and from 0.55 to 0.15 eV, respectively, when TS increased from room temperature to 448 K (film thickness = 100 nm). The Mott and Davis model for the density of states in amorphous solids was used to interpret and discuss the results.

Thin films of As46Te46S8 with different thicknesses were prepared via thermal evaporation onto chemically cleaned glass substrates at different temperatures. X-ray diffraction of the deposited film at room temperature revealed the formation of an amorphous structure. In addition, the selected-area electron diffraction (SAED) patterns confirmed the amorphous phase. The mechanism of the optical absorption was observed to follow the rule of direct transition. An increase in the optical gap (E0) from 2.35 to 2.73 eV was observed when the substrate temperature TS was varied from room temperature to 463 K (film thickness = 100 nm). In addition, E0 was observed to be dependent on the film thickness and increased from 1.7 to 2.38 eV when the film thickness was increased from 35 to 135 nm (TS = room temperature). The effect of TS on the electrical properties was also studied. The electrical resistivity (ρ) and the activation energy for conduction ( E ) decreased from 7.74 x105 to 6.81 x 102 Ω cm and from 0.55 to 0.15 eV, respectively, when TS increased from room temperature to 448 K (film thickness = 100 nm). The Mott and Davis model for the density of states in amorphous solids was used to interpret and discuss the results.

Previous studies have examined the effects of gamma-radiation on Japanese fish, in particular medaka(Oryzias latipes). In the present work, alterations in erythrocytes were recorded as haematological bio-indicators of exposure to gamma-radiation. After exposure of medaka fish to two different doses ofradiation (2 Gy and 10 Gy), many malformations in red blood cells were observed in the irradiatedfish compared with control fish. These malformations included acanthocytes, crenated cells, amoeboidcells, and sickle cells. More malformations were seen at the higher radiation dose. No micronuclei wereseen in any group, but nuclear abnormalities were observed. We conclude that gamma-radiation causesmorphological malformations of erythrocytes and is harmful to medaka fish.

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Adsorptive stripping voltammetry of antibiotics of rifamycin SV (RSV) and rifampicin (RIF) was investigated by cyclic voltammetry and differential pulse voltammetry using a renewable pencil graphite electrode (PGE). The nature of the oxidation process of RSV and RIF taking place at the PGE was characterized. The results show that the determination of highly sensitive oxidation peak current is the basis of a simple, accurate and rapid method for quantification of RSV and RIF in bulk forms, pharmaceutical formulations and biological fluids by differential pulse adsorptive stripping voltammetry (DPASV). Factors influencing the trace measurement of RSV and RIF at PGE are assessed. The limits of detection for the determination of RSV and RIF in bulk forms are 6.0 × 10–8 mol/L and 1.3 × 10–8 mol/L, respectively. Moreover, the proposed procedure was successfully applied to assay both RSV and RIF in pharmaceutical formulations and in biological fluids. The capability of the proposed procedure for simultaneous assay of antibiotics RSV-isoniazid and RIF-isoniazid was achieved. The statistical analysis and calibration curve data for trace determination of RSV and RIF are reported.

Sulfated zirconia catalysts were prepared by wetness impregnation of zirconium hydroxide with an aqueous solution of (NH4)2SO4 with SO42− loadings (1–30%, w/w) and calcined at 450 °C for 3 h in a static air atmosphere. The catalysts were characterized by FT-IR, XRD, TEM and BET measurements. The surface acidity of the catalysts was investigated by the dehydration of isopropanol and the adsorption of pyridine (PY) and 2,6-dimethyl pyridine (DMPY). The catalysts were tested for dehydration of methanol in a fixed-bed reactor at 230 °C using air as a carrier gas. The results revealed that among different catalysts, 10% SO42− supported onto zirconia showed the highest catalytic activity with 83% conversion and 100% selectivity toward dimethyl ether. A good correlation was found between the acidity of the catalysts and their ability to dehydrate methanol.

Sulfated zirconia catalysts were prepared by wetness impregnation of zirconium hydroxide with an aqueous solution of (NH4)2SO4 with SO42− loadings (1–30%, w/w) and calcined at 450 °C for 3 h in a static air atmosphere. The catalysts were characterized by FT-IR, XRD, TEM and BET measurements. The surface acidity of the catalysts was investigated by the dehydration of isopropanol and the adsorption of pyridine (PY) and 2,6-dimethyl pyridine (DMPY). The catalysts were tested for dehydration of methanol in a fixed-bed reactor at 230 °C using air as a carrier gas. The results revealed that among different catalysts, 10% SO42− supported onto zirconia showed the highest catalytic activity with 83% conversion and 100% selectivity toward dimethyl ether. A good correlation was found between the acidity of the catalysts and their ability to dehydrate methanol.